Delta weird miscalibration (SOLVED)

Hello,

I own a Mini Kossel for more than a year now and I think I know pretty much everything that is needed to know about deltas, but I cant deal with this problem. The story : I calibrate the printer with manual paper calibration method, at every tower at Z 0.00 the paper is dragging just a bit and also at X0 Y0. Then I calibrate the rod length E steps.... I print a few things (3-5 models) and I just home the printer and for fun I check if the paper is dragging the same at Z 0.00, I send the command And the nozzle just rams into the glass like 40 ton truck. Glad i didnt start a print! Then i cut off the power, home again and try Z 1.00 and stepping lower by 0.1mm. And the paper drags at Z 0.7mm. HOW can this be ? It was perfect before a few hours. So before posting anything, here is what I know and what I was thinking about : Le machine = Mini Kossel, Smoothieboard, sliders not rollers, GT2 belts, 1.7A 100step/mm steppers... So what I tried and checked, the endstop switches cant move, the belts arent loose, the hotend isnt loosely screwed, the sliders are good, the glass didnt move, the software wasnt changed, the paper isnt 0.7mm thick

If u would have any idea it would be really helpful, Thanks for everyone who just had the time to read this

UPDATE! I recently found out that I am dumb, I checked every possible mechanical and electronical issue that could do this, but when I turned the lights on, a small filament leak was in the nozzle -_- Sorry for this whole post (couldnt find a delete post button )

Edited 1 time(s). Last edit at 11/29/2015 08:58AM by Shepard48.

Always calibrate with heated nozzle...
Not just because of the ooze droplet that freaked you out, but the thermal expansion too
-Olaf

Edited 1 time(s). Last edit at 11/29/2015 10:29AM by o_lampe.